Gravity-type filtration systems have been used for a number of years to filter particulate from liquids. In general, particulate laden liquid is spread across the width of filter media such that the liquid flows through the media while the particulate is caught within the media to form a cake. As the cake builds, liquid flow is restricted and the fluid level rises on top of the caked particulate to form a pool. Once the fluid level in the pool reaches a predetermined height, the apparatus will shift the media so that liquid again flows across an unobstructed portion of the media.
While these gravity liquid filtration devices have been known for some time, they still suffer several problems. First, prior art filtration systems have utilized a supply of filter media on a reel, which is fed through the filter system, and then cleaned and wrapped on another reel for reuse, or discarded. In order to avoid these problems, an endless filtration system is desirable, which utilizes an endless, continuous loop belt of filtration media which is initially utilized for filtering, washed, and then returned for reuse in the same system.
Because the use of an endless media continuous loop belt requires that one flight of the belt return under the filtering pool, it is desirable to redirect liquid flow from the filtering pool to avoid contamination of the clean fluid.
Another problem with existing endless loop filtration systems is in the cleaning of the filter media.
Finally, endless filter media filtration systems are more prone to sliding or dislodgment of the filter media belt from the carrier belt. In addition, the filter media belt can become wrinkled, which reduces the filtering capacity of the filter media.